Robert, off the top of my head, you'll probably want to make the sort_buffer_size as large as you can, keeping in mind that this memory setting is allocated per thread. In other words, if you have up to 32 threads, and you allocate 100 MB to this setting, you could eat up 3200 MB this way if enough operations happened simultaneously.
An excellent boost from a hardware perspective would be to either 1) set up your temp dirs on a RAM disk, though that can be problematic for replication 2) set up your temp dirs on a dedicated set of fast, striped disks See http://dev.mysql.com/doc/refman/5.0/en/server-system-variables.html and http://dev.mysql.com/doc/refman/5.0/en/temporary-files.html On 10/17/06, Robert DiFalco <[EMAIL PROTECTED]> wrote:
I have an unavoidable filesort in a very large query. Can someone point me to references for optimizing filesort? I'm assuming this is going to be changes to my.ini or the hardware. TIA, R. -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED]
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